Put ChefSpec Angel on service shoulders
ChefSpec: Disable Riak until cookbook is fixed
Disable autostart of Redis and Memcached services

Without this change, Redis and Memcached services are enabled on boot,
which is not expected.

Without this change, MySQL service activation on boot was not controlled
by Chef provisioning, but only relying on 'mysql-server' apt package
behavior.
Merge pull request #226 from gildegoma/add-chefspec-for-services

Put ChefSpec Angel on Service Shoulders